When soft tissue such as a ligament or a tendon becomes detached from a bone, surgery is usually required to reattach or reconstruct the tissue. Often, a tissue graft is attached to the bone to facilitate regrowth and permanent attachment. Various fixation devices, including sutures, screws, staples, wedges, and plugs have been used in the past to secure soft tissue to bone. In typical interference screw fixation, for example, the soft tissue or graft is fixed to the bone by driving the screw into a blind hole or a tunnel in the bone while trapping the end of the graft or tissue between the screw and the bone tunnel. In other methods, the graft is simply pinned against the bone using staples or sutures tied around the end of the graft to the bone.
More recently, various types of threaded suture anchors have been developed. The application of such suture anchors generally requires the surgeon to tie knots in the suture to secure the tissue to the bone, which is tedious and time-consuming. The surgical procedure would be less cumbersome for the surgeon and ultimately more beneficial to the patient if the tissue could be attached to the bone without the surgeon having to tie suture knots.